Is it possible to watch imm4 codec encoded videos in Ubuntu?
The imm4 codec is a restricted codec - covered by patents, so for some countries you should check if you are covered to run this decoder.
note I've tested this on 11.10
Install the restricted Medibuntu repository:
Now install mplayer and w32codecs
Now the important part - mplayer is coded to look for the windows DLL VCMIMM4.dll, however, medibuntu installs a lowercase version that mplayer would not recognised out-of-the-box. Thus to fix this, create a VCMIMM4.dll file in the codecs folder.
Now play your video - e.g.